The present invention relates to a method of dispensing accurately small amounts of high
viscosity lubricant components using tubeless positive-displacement liquid-handling equipment for forming
lubricant blends. The method includes the steps of: providing a low
void volume positive displacement
pipette with a tapered tip for each
lubricant component contained within a lubricant additive reservoir, and one or more lubricant blend containers; ingesting into a low
void volume positive displacement
pipette from a lubricant additive reservoir an
ingestion volume of a lubricant component; moving the low
void volume positive displacement
pipette from the lubricant additive reservoir to the one or more lubricant blend containers; ejecting into the one or more lubricant blend containers an ejection volume of the lubricant component from the low void volume positive displacement pipette; returning the low void volume positive displacement pipette from the one or more lubricant blend containers to the additive reservoir; and repeating these steps for each additional lubricant component. The advantages of the method of the present invention include improved dispensing accuracy, quicker dispensing, lower
shear rate during dispensing, lower temperature for dispensing, less residual additive on the tip of the device after dispensing, and the ability to real time monitor density and
mass during dispensing. The method finds application in
laboratory test environments, and in particular in high
throughput testing environments.